Connecting rods are used in various kinds of pumps used in oilfield operations. A connecting rod can be used, for example, in a reciprocating pump. The reciprocating pump can be used to pump fluid such as chemicals, cement, or other media into a well. Reciprocating pumps typically increase the pressure within a cylinder by reciprocating a plunger longitudinally within the cylinder. The connecting rod typically has a body and two ends. The crosshead end has a hole that allows the end to be connected to a crosshead, which is connected to a pony rod, which in turn is connected to the plunger. The other end secures to a crankshaft that rotates.
The crosshead reciprocates within a crosshead housing and has a concave cavity that receives the crankshaft end of the connecting rod. To secure the end of the connecting rod to the crosshead, a wrist pin is inserted through the hole formed in the crosshead end of the connecting rod. The wrist pin thus pivotally secures the end of the connecting rod to the crosshead and allows for the translation of the crankshaft's rotational movement into linear movement of the crosshead and thereby the plunger. The wrist pin is an additional part that may need to be replaced during the life of the pump. Further, the wrist pin adds weight to the overall pump weight, which can make the transportation of reciprocating pumps more difficult and expensive. Also, disconnecting the connecting rod from the crosshead requires driving the wrist pin out.
Thus, it would be desirable to provide a connecting rod for use in reciprocating pumps that does not require a wrist pin to secure an end of the connecting rod to a crosshead.